HISTORY OF CALIFORNIA. 



239 



as 12J, which is that of a mineral called electrum, 

 which will be described presently, and which is a mix- 

 ttire of silver and gold. 



When a piece of gold is broken (which is not done 

 without difficulty greater in proportion to its purity,) 

 the fractured edges are very uneven and torn, exhibit 

 ing a peculiar fibrous appearance, known to mineralo 

 gists as u fine hackly." This fracture indicates that 

 the mineral is torn asunder and not really broken, 

 and is a proof of considerable toughness. 



The form in which gold is found is various. It is 

 sometimes crystalline, in eight or twelve-sided regular 

 figures, passing into cubes, but the crystals are gene 

 rally small and rare. In case of such crystals being 

 found, it is well worth knowing that they possess a 

 value as mineral specimens far beyond that of the 

 gold which they contain. 



More frequently the metal is found in lumps or 

 grains, called by the Spaniards pepitas, varying in 

 size from that of a pin's head to masses weighing, as 

 has been already mentioned, nearly one hundred 

 pounds troy. The term pepita is only applied to 

 grains of some magnitude, and the most common 

 limits of size are from that of a small pin's head to 

 that of a nut or gooseberry. 



When much smaller and still rounded, they are 

 called gold dust, and when flattened, scales or span 

 gles. In nature, and when seen in veins of quartz, 

 gold often occurs foliated, or* in leafy expansions of 

 extreme thinness, or in branchy (dendritic) forms, 

 probably made up of minute crystals. It is in the 

 form of very minute grains that the metal is generally 

 disseminated through rocks and auriferous ores of 

 various metals, and these are reduced according to 



